Process for breaking petroleum emulsions



i for resolving-petroleum emulsions of the water-in-oil type foots. oralkylate detergent bottoms.

one dodecyl benzene radical'and another radical having PROCESS FORBREAKING PETROLEUM EMULSIONS Melvin De Groote, University City, andAlvin Howard S mith, Glendale, Mo., assignors to Petrolite Corporatlon,Wilmington, Del. a corporation of Delaware No Drawing. ApplicationAugust 3, 1955 9 Serial No. 526,330

27 Claims. (Cl. 252-332) The present invention relates to processes orprocedures particularly adapted for preventing, breaking, or resolvingpetroleum emulsions of the water-in-oil type, and particularly petroleumemulsions.

Our invention provides an economical and rapid process that arecommonly'referred to as cut oil, roily oil,

emulsified oil, etc., and which comprises fin'e droplets ofnaturally-occurring waters or brines dispersed in a more or lesspermanent state throughout the oil which constitutes the continuousphase of the emulsion.

, It also provides an economical and rapid process for separatingemulsions which have been prepared under controlled conditions frommineral oil, such as crude oil and relatively soft waters or weakbrines. Controlled emulsification and subsequent demulsification underthe conditions just mentioned are of significant value in removingimpurities, particularly inorganic salts, from pipeline oil. r e

- The present invention is concerned with a process for breakingpetroleum emulsions of the water-'i'n-oil type characterized bysubjecting theemulsion to the action of a demulsifying agent comprisinga mixture of at least I 60% by weight and not over 90% by weight of (A)a conventional aromatic solvent-soluble non-ionic demulsifier, and atleast 10% by weight and not over 40% by weight of-(B) ammonium saltsobtained by monosulfonation and neutralization of a sulfonatable mixtureconsisting of (a) nonyl phenol foots characterized by a dinonyl phenolto nonly phenol ratio within the range of 2:1

to 3:1 and containing not less than 90% of nonylated phenols and (b)dodecyl benzene bottoms consisting essentially of didodecyl benzene andother polyalkylated benzenes. For convenience such bottoms will bereferred to by customary trade name, to wit, alkyl'ate detergent i Thereis produced a large amount of aproduct Which is essentially monododecylbenzene. This product is frequently referred to as detergent alkylateThe reason isthat the product is subjected to monosulfonation followedby neutralization to give one of the most important commercial syntheticdetergents. In the alkylation of benzene there is produced somedialkylated, and possibly even trialkylated, benzene. For the most partthe dodecyl benzene foots consist essentially of didodecyl benzene andother polyalkylated benzenes. It is possible that in some instancesthere is introduced into the aromatic nucleus a fewer number of carbonatoms, for instance, 6 or 8.

i As to a further description ofsuchdodecyl bottoms of facts seeIndustrial'and Engineering.Chemistry,' vol. 46, No. 11, page 248, 1954,and U. S. Patent No. 2,671,762, dated March 9, 1954, to Wisherd.Attention is directed to the fact that the aforementioned Patent U. S.2,671,762 not only describes the sulfonation and neutralization of thebottoms produced in'det'ergentalkylate manufacture but also the use ofsuch product for the resolution ofpetroleum emulsions of thewater-in-oil type. Needless to in-oil type.

' 2,828,267 Patented Maru'ZS, 1958 I ce say detergent alkylate foots canbe sulfonated by the use of oleum, sulfur trioxide, or the like, in thesame manner as is employed in the sulfonation of dodecyl benzene or morehighly alkylated benzenes including keryl benzene.

The nonionic demulsifiers of the kind described are well known andnumerous examples will be included subsequently. Nonyl phenol footsconsisting largely of dinonyl phenol and sometimes referred to asdinonyl phenol crude or as nonyl phenol bottoms has been available onlyrecently as a commercial product. The reason is as follows: Nonyl phenolis finding substantial use in the form of its ethylene oxide additionproduct as a synthetic detergent. The nonyl phenol used for this purposeis preferably colorless and free from dinonyl phenol. In the alkylationof phenol to produce the nonyl phenol there is invariably produced somedinonyl phenol. The nonyl phenol is removed by distillation. Theresidual product referred to as nonyl phenol bottoms, nonyl phenolfoots, or as crude dinonyl phenol, depending on its method ofmanufacture, may contain as much as of dinonyl phenol and as little as25% of nonyl phenol. A product obtained from another manufacturercontained approxi mately 65 dinonyl phenol and 35% nonyl phenol. Varioussamples contain the two phenols in amounts equivalent to 100% of theproduct. The commercially available product appears to contain little orno trinonyl phenol but may have some polymerized nonylene or the like. Atypical example of commercially available product is characterized bythe following:

Physical form Viscous amber liquid;

Boiling point 5% (760 mm.); over 325. C. Hydroxyl number -165. Specificgravity At 25/25 (3.: -92.

For the above reason we are not aware whether sulfo nated nonyl phenolfoots have been described in the patent literature or elsewhere and forthis reason there will be included a'complete description of the monosulfona-v 'tion followed by conversion into the ammonium salt. i Forconvenience what is said hereinafter is divided into five parts sideredas a single component as far as composition with the nonionicdemulsifier is concerned.

Part III is a description of conventional aromatic sol; vent solublenonionic demulsifiers used as one of the two components in the mixturewhich exemplifies the present process. Part IV is concerned withsuitable mixtures of the materials described in Part II and Part IIIprecedingto yield the demulsifiers as here employed. 7 Part V isconcerned with the use of said demulsifiers for the resolution ofpetroleum emulsions of the water- PART I In our co-pending applicationSerial No. 52

6,329, filed August 3, 1955, the following text concerned with the useof sulphonates derived from nonyl phenol foots applies with equalforce'to the present mixture wherein the sulphonate employed is inreality derived not only from nonyl phenol foots but by the use ofdetergent alkylate foots in combination. The-text of said co-pendingappli;

cation statesr V The use of sulfonates for resolution of petroleumemulsions'is well known, See U. S. Patent 1,299,385, dated April 1,1919, to Rogers. It is noted in said "patent that it was concernedprimarily with the use'of sulfonates obtained from mineral oil. Over aperiod of years although a large number of petroleum sulfonates havebeen used in demulsification either as the sole component of thedemulsifier or in admixture with other Well known demulsifiers it hashappened that for many years the overwhelming percentage of suchmaterial, probably more than 90% consumed as demulsifiers, happened tobe oil soluble type or mahogany acid soap type.

For a number of years it has been recognized that al-- though thecomposition of mahogany soaps might vary, and undoubtedly does vary, abetter understanding of the oil solubility of hydrocarbon sulfonates isobtained by a study of alkylated aromatic sulfonates.

U. S. Patent 2,448,184, dated August 31, 1948, to Lemmon states:

Sulfonated alkyl aromatic hydrocarbons have been widely used as wetting,washing, emulsifying and detergent agents. Depending upon the length ofthe alkyl chain of the alkyl substituent, the sulfonated alkyl aromatichydrocarbons are either preferentially watersoluble or preferentiallyoil soluble. For example, alkyl benzene sulfonates in which the alkylgroup contains from about to about carbon atoms are preferentiallywater-soluble and are useful as wetting and/or dtergent agents. Thehigher alkyl benzene suifonates, that is, alkyl benzene sulfonatescontaining more than 16 carbon atoms and usually from about 18 to about30 carbon atoms in the alkyl groups, are preferentially oilsoluble.These preferentially oil-soluble alkyl aromatic sulfonates in manyrespects resemble the preferentially oil-soluble sulfonates obtained inthe treatment of petroleum oils With concentrated or fuming sulfuricacid. These preferentially oil soluble petroleum sulfonates, because oftheir characteristic color are generally referred to as mahogany soapsalthough certain preferentially oilsoluble petroleum sulfonates having acharacteristic brownish color are called brown acid soaps.

Thus, oil soluble petroleum sulfonates obtained in the manner describedin the aforementioned U. S. Patent 2,448,184 are obviously a substitutefor mahogany soap for a variety of purposes for which mahogany soaps areordinarily used.

In the aforementioned U. S. Patent 2,448,184 it was also pointed outthat hydroxy compounds, i. e., phenols can be sulfonated in the mannerdescribed. The patent states:

The present invention can be applied to a wide variety of alkyl aromaticcompounds in which the alkyl substituent has at least 18 carbon atoms inthe chain. The aromatic nucleus can be, for example, benzene, toluene,xylene, cumene, naphthalene, methyl naphthalenes, ethyl naphthalenes,isopropyl or alkyl naphthalenes, diphenyl, alkyl phenyls, anthracene,and alkyl anthracene. Halogen, nitro, hydroxy or other derivatives ofthe aromatic hydrocarbons can also be sulfonated in accordance with thepresent invention.

The process described in said aforementioned U. S. Patent 2,448,184involves the use of anhydrous sulfur trioxide. See claim 1. However, itis known that when sulfur trioxide is employed that changes may takeplace in the side chain or side chains. See British Patent 664,- 577which in discussing sulfonation of an alkyl aromatic hydrocarbon statesas follows:

The difficulties associated with the sulfonation of long chainalkylaromatic hydrocarbons are especially acute in the case ofpoly-substituted benzenes, for example the long chain alkyl toluenessuch as dodecyltoluene. The introduction of a sulfonic group into thenucleus tends to displace the long chain alkyl group, particularly if itis tertiary and to lesser extent if it is secondary. This displacement,which is negligible with monoalkyl benzenes, is increased as thetemperature increases, and may reach as high as 20 percent in the caseof p-tertiary dodecyl toluene above 40f C. The displacement, or dealkylation is accompanied by complex side reactions in- 4 volvingoxidation, hydrogen-transfer, and tar formation, with accompanyingsulfonation of both the tar and the dealkylated benzene nucleus, thatare reactions which are all undesirable in the manufacture of highquality detergent sulfonic acids.

in light of the lack of specificity in regard to the composition ofmahogany soaps and in regard to oil soluble sulfonates obtained by thesulfonation of alkylated aromatics particularly alkylated benzene, thenthe introduction of 18 carbon atoms or more, a single side chain or morethan one side chain generally yields oil soluble sulfonates. Needless tosay, in the case of a phenol if one introduces three alkyl radicals itmight be more difiicult to sulfonate than if the product were mono ordisubstituted and thus tend towards the increased production ofby-products.

For the above reason although as stated it is not known whethersulfonated nonyl phenol foots or bottoms have been described and alsonot withstanding the fact that the total number of carbon atoms in theside chain may be somewhat less than the normal borderline, i. e., about15 carbon atoms instead of 18 and not withstanding the fact that thehydroxyl radical does contribute a hydrophile effect, even so no claimis made in regard to these herein described sulfonates alone asdemulsifiers. Likewise no significance is attached to the abovestatement that the alkyl carbon atoms even where there are as many as 18present are divided into two alkyl chains. Even so the invention is notconcerned with the use of another oil soluble sulfonate as such but toits use in combination with the components of a demulsifying mixturedescribed in Part III following. In such mixture as will be pointed outin Part IV following the effectiveness of the sulfonate is to be foundlargely in introducing an anti-sludging property in the sense that whendemulsification does take place by means of a mixed demulsifier, acomparatively clean interface is obtained at the interface surfacebetween the oil and water layer, or at least a bright transparent upperoil layer.

Typical detergent alkylate foots have the following properties:

ASTM D-158 Engler Distn.: Foots or bottoms R With l-inch immersionthermometer. See aforementioned refere2ne to Industrial EngineeringChemistry, volume 46, page PART II As previously pointed out, thesulphonation of the mixed phenol foots-detergent alkylate foots isconventional and one can use any one of a number of acceptablesulphonating agents such as sulphur trioxide, oleum, etc. The acidicmass is then neutralized with anhydrous ammonia or a commercial aquaammonia. The following examples 1a through 12a illustrate the procedure:

Example I a A 100 lb. charge consisting of nonyl phenol foots and 20%detergent alkylate foots was placed in a conventional sulphonator. Thephenol foots consisted of assess? approximately 75% dinonyl and 25%nonyl phenol. For a description of a typical sulphonator, see UnitProcesses in Organic Synthesis, Groggins, 4th ed.,

McGraw-Hill, New York, 1952, page .266. The batch was agitated while 55lbs. of 25% ol-eum were run in. The oleum addition was controlled so asnot to produce a temperature higher than 80 C. After this, the batch wasagitated for 1 hour and then cooled back to 40 C. 28 pounds of waterwere added and the batch allowed to settle overnight. When the spentacid had been withdrawn, a yield of 123 pounds of sulphonic acidremained.

Example 2a 7 i In this example the crude nonyl phenol foots contained.about 65% dinonyl phenol and 35% nonyl phenol. 80

pounds of the phenols were mixed with 20 pounds of detergent alkylatefoots. The sulphonator used was the same as described in Example 1a,preceding. The batch was sulphonated at 80 C. as before with 65 poundsof 25% oleum. After being washed with 35 pounds of water and settledovernight, the sulphonic acids were recovered by drawing off the spentacid. The yield was 128 pounds. Solvents were added together with 30pounds of ammonium'hydroxide. The active sulphonate contained 14.5%combined 80;, plus 1.5 free S The batch was adjusted to 75 active withsolvent and appeared to have properties very similar to the sulphonatein Example 1a.

Example 3a A mixture of crude phenol and keryl benzene residuewassulphonated exactly as in Example 2a, with identical amounts ofreactants. The crude phenol consisted of 68% dinonyl phenol, 25% nonylphenol, and 7% of non phen'olic matter. The non-phenols were assumed toi be aromatic hydrocarbons and perhaps some polymerized nonenes. Thedetergent alkylate foots was the same as used in Example 2a. The yieldof sulphonic acid was 126 pounds. The active material contained 15%combined S0 plus 2% free S0 The ammonium sulphonates were soluble'inXylene, kerosene, alcohol, and simil'ar solvents. The sulphonate wasadjustedto 75% of active material with an aromatic solvent.

7 Example 4a a The crude phenol'detergent alkylate foots mixture'ofExample la was sulphonatedwith anhydrous sulfur trioxide. The reactorused was similar to the type described in British Patent 664,577 toNewby, January 9, 1952. 100 pounds of mixturewas held at 75 C. while15.5 pounds of sulphur-trioxide gas was run in over a twohour period.The S0 gas was diluted with 9 volumes of dry air. A yield of 115 poundsofsulphonic acids was obtained, containing 12.3% combined S0 and 0.7%free 80 Solvent was added in an amount such that a 75% active sulphonateremained after neutralization with 26.5 pounds of ammonium hydroxide.The product was slightly more viscous and darker than that of Example1a, but otherwise substantially identical. p

Example 5a The crude mixture of Example 2a was usedin this case. 100pounds was chargedto the sulphon-ator together with 30 pounds of mineralspirits. The solvent was" added merely to'reduce viscosity and took nopart in the sulphonation. 16% pounds of gaseous 80 diluted with 9volumes of dry air was admitted over'a two-hour period.- The yield was11-6- pounds of sulphonic acids containing 13% combined S0 and 0.5% freeS0 27.8 pounds of ammonium hydroxide was required for neutralization.Additional solvent was added to give a product containing 75 ammoniumsulphonates.

Example 6a The procedure used in Example 1a was followed here. The batchconsisted of two parts of this crude nonyl phenol and one part of thedetergent alkylate foots. The sulphonates contained 14% combined andwere somewhat less viscous than those in Example la.

Example 8a Example 2a was repeated. The batch used consisted of,

two parts crude phenol to one part detergent alkylate foots. Thesulphonates contained 15% combined S0 Example 9a Example 3a wasrepeated. The batch used consisted of two parts crude phenol to one partdetergent alkylate foots. The sulphonates contained 15% combined S0Example 10a Example 4a was repeated. The batch consisted of two partscrude phenol to one part detergent alkylate foots. An additionalonepound of 80;, was used. The sulphonates contained 13% combined S0 andwere somewhat less viscous than the sulphonates of Example 40.

Example 11a Example 5a was repeated. The batch consisted of two partscrude phenol to 1 part detergent alkylate foots. An additional 1.5pounds of S0 was used. The sulphonates contained 13.5% combined S0Example 12a Example 651 was repeated. The batch consisted of two,

parts crude phenol to one part deter-gent alkyl-ate foot's. Anadditional pound of S0 was used. The sulphonates contained 14% combinedS0 PART III As previously stated the demulsifying agents employed in thepresent vprocessare obtained by mixing ammonium sulfonates of the kinddescribed elsewhere in this specification with conventional nonionicaromatic soluble de-' mulsifiers. Conventional noniom'c demulsifiers areobtained by a reaction with ethylene oxide, propylene oxide, butyleneoxide, and glycide. The initial reactant may be a water soluble productsuch as alcohol, alkylated phenol, an amide, acid, or the like. Suchreact-ants may and usually do contain at least one radical having notless than 8 uninterrupted carbon atoms.

In some instances, however, one may start withwater' soluble substancesfor instance low molal glycols such In such instances the manufacture ofthe conventional nonionic demulsifying agent invariably involves theuse.

of either propylene oxide or butylene oxide or both along with eitherethylene oxide or glycide or both. Some conventional nonioni-cdemulsifiers may have free carboxyl radicals or maybe obtained by linearpolymeriz-a- The product was soluble in xylene, kero Such products arecharacterized by the fact,

"7 tion between a low molal dicarboxy acid and an alkylene oxidederivative. The unneutralized carboxyl group does not introduce anymeasurable anionic surf-ace active properties.

In some instances effective conventional demulsifying agents are madewhich are initially hydrophile in character comparable to ordinaryhousehold liquid detergent. They are insoluble in aromatic hydrocarbonswhich is understood to mean a non oxygenated hydrocarbon aromaticsolvent such as benzene, toluene, xylene, high boiling solvent derivedfrom coal tar, cracking of petroleum, hydrogenated coal, etc. A largenumber of conventional nonionic demulsifying agents are soluble in thearomatic solvent of the kind described. For example one can readilyprepare a solution of 10 parts of such conventional demulsifier byWeight and 100 parts of xylene by weight at ordinary or slightlyelevated temperatures.

The present invention is limited to such aromatic solvent solublenonionic demulsifiers.

Demulsifiers of the type referred to immediately preceding are describedin a number of patents. See U. S. Patent No. 2,499,365, dated March 7,1950, to De Groote and Keiser. Still another type are the kind describedin U. S. Patent No. 2,562,878, dated August 7, 1951, to Blair.

Other types are obtained by the oxyethylation of polypropylene-glycols.See U. S. Patent No. 2,674,619, dated April 6, 1954, to Lundsted.

See also U. S. Patent No. 626,942, dated January 27,

1953, to De Groote; U. S. Patent No. 2,629,704, dated February 24, 1953,to De Groote et al.; U. S. Reissue Patent No. 23,851, dated July 13,1954, to De Groote et al.; U. S. Patent No. 2,629,706, dated February24, 1953, to De Groote et al.; U. S. 2,549,434, dated April 17, 1951, toDe Groote et al.; U. S. 2,552,528, dated May 15, 1951, to De Groote; andU. S. 2,552,529, dated May 15, 1951, to De Groote.

Typical conventional nonionic aromatic solvent soluble demulsifiers areindicated in the following table:

TABLE I Example Description of aromatic solvent soluble nonionic N 0.demulsifiers 1b See EXBEDIG 18C in aforementioned U. S. Patent No. 2,26,9 2b SeQefifiExgfaple 26C in aforementioned U. S. Patent No.

, e, 2. 3b See gxginple 43C in aforementioned U. S. Patent No.

2. 4b See demulsifier defined by claim 3 of aforementioned U. S.

Patent N 0. 2,629,704. 56 See demulsifying agent defined by claim 5 ofaforementioned U. S. Patent No. 2,629,704. 6b See demulsifying agentdefined by claim 6 of aforementioned U. S. Patent No. 2,629,764. 7b Seedemulsifying agent defined by claim 3 of aforementioned Reissue PatentU. S. 23,851. 8!) See demulsifying agent defined by claim 4 ofaforementioned Reissue Patent U. S. 23,851. 9!) See demulsifying agentdefined by claim 5 of aforementioned Reissue Patent U. S. 23,851. 10!)See demulsifying agent defined in claims 3, 4 and 5 of aforementioned U.S. Patent 2,629,706. 111) See demulsifying agent defined in claim 9 ofaforementioned patent U. S. 2,562,878 and derived frompolypropyleneglycol molecular weight, 2,000. 120 See demulsifying agentdefined in claim 9 of aforementioned patent U. S. 2,562,878 and derivedfrom polypropylene glycol molecular weight 2,250. 136 See demulsifyingagent defined in claim 9 of aforementioned patent U. S. 2,562,878 andderived from polypropylene glycol molecular weight 2500.

See demulsifying agent defined in claim 9 of aforementioned patent U. S.2,562,878 and derived from polypropylene glycol molecular weight 2,750.

See industrial pamphlet Pluronics of Wyandotte Chemical Corporation,Wyandotte, Michigan. Pluronic L72. See also aforementioned U. S. Patent2,674,619.-

See industrial pamphlet Pluronics of WyandotteChen-iical Corporation,Wyandotte, Michigan. Pluronic See also aforementioned U. S. Patent2,674,619.

See industrial pamphlet Pluronics of Wyandottc Chemical Corporation,Wyandotte, Michigan. Pluronic L64. See also aforementioned U. S. Patent2,674,619.

See industrial pamphlet Pluronies of Wyandotte Chen:-

ical Corporation, Wyandotte, Michigan. Pluronic L3l. See alsoaforementioned U. S. Patent 2,674,619.

See industrial pamphlet Pluronies of Wyandotte Chemical Corporation,Wyandotte, Michigan. Pluronic L-61. See also aforementioned U. 5. Patent2,674,619.

TABLE I--Continued Example Description of aromatic solvent solublenonionic No. demulsifiers 20!) See industrial pamphlet Pluronics ofWyandotte Cl1cmcal Corporation, Wyandotte, Michigan. Pluronic L81. Seealso aforementioned U. S. Patent 2,674,619.

211) See industrial pamphlet Plur'onics of Wyandotte ChemicalCorporation, Wyandotte, Michigan. Pluronie L42. See also aforementionedU. S. Patent 2.674,6l9.

22b See industrial pamphlet Pluronics of Wyandotte Chemical Corporation,Wyandotte, Michigan. Pluronie L33. See also aforementioned U. S. Patent2,674,619.

23') See Example B in aforementioned U. S. Patent 2,549,434.

Propylene oxide added first, then ethylene oxide.

240 See Example E in aforementioned U. S. Patent 2,549,434.

Propylene oxide added first, then ethylene oxide.

25!) See Example C in aforementioned U. S. Patent 2,549,434.

Propylene oxide added first, then ethylene oxide.

26') See Example M of aforementioned U. S. Patent 2,552,529.

Propylene added first, then ethylene oxide.

27!) See Example 25 of aforementioned U. S. Patent 2,552,528.

Norn.--Pluronics is the trademark of Wyandotte Chemicals Corp. toidentify products of the kind described in aforementioned U. S. Patent2,674,619.

PART IV Dernulsifiers are ordinarily used in concentrations ofapproximately to 80%. The purpose is to supply the demulsifier in theform of a liquid which can be employed by means of a metering pump orother measuring device. Since solvent is usually present in the finalmixed product We have found it more convenient to make a solution of theammonium sulfonate and the nonionic demulsifierseparately in a highboiling aromatic solvent. Generally, a to solution is used. The twosolutions are then mixed so as to give the desired ratio between the twocomponents and have a suitable solvent present. Nore solvent can beadded if desired. Hereto attached Table II illustrates a variety ofsuitable mixtures.

TABLE II.MIXED DEMULSIFIER [Ammonium sulfonates used is indicated bydesignation 1a, 2a, ete. in parentheses. The nonionic demulsifier usedis indicated by the designation 1b, 212, etc. outside the parentheses."lhe percentage by weight of ammonium sulfonates used is indicated atthe head of the column and the remainder is nonionic demulsifier.Percentage by weight is on solvent free basis] 1b (1 1) M M N 1H (7 5(4a) 11 M g M 0M) 11b( (4 M 11) 13!? 141) (1 1 (4 M 1 200 (111) 21b( M(5c) M (l M (3 22b( PART V admixture with other conventionaldemulsifiers. The

herein described demulsifiers are indeed primarily to use as suchwithout further formulation.

It has been previously pointed out that the efiectiveness of the hereindescribed demulsifier is its ability to break oil field emulsions underconventional conditions without sludge and at the same time yieldingbright pipeline oil, i. e., pipe line oil that is free from the minutetraces of foreign matter, whether suspended water or suspended emulsiondroplets, that are due to non-resovable 10 made to explain the efiectobtained by the added anionic ammonium sulfonate. In some instances thehaze in the upper layer pipeline oil and the sludge of the interface isnot a refractory emulsion. As has been stated previously in theresolution of petroleum emulsions one sometimes obtains a sludge in theinterface. This sludge may be of two different types or, for thatmatter, a mixture of two. One type is non-resolvable sludge. It consistsof exceedingly fine iron oxide or sulfide or other solids as describedhereinafter. l insolubles. Furthermore, the insolubles may be organicAppearance N H4 Appearance Appearance Test Demuls. Demuls Mixed sul-Non- No. temp ratio demuls. ionate ionic F. a used 011 Interalone 011phase Interface alone Oil phase Interface phase face la. 70 1:12, 500 1cBright Sharp to No treatment... No treatment... Bright Heavy sludge. 2d70 1:10, 000 7c do d0 5:: do do 80 do Do.

70 1:8, 000 11c do do.. 411 do 11b Slight haze Light sludge.

in 150 1:8, 000 18c do do Go do 19b Bright Heavy sludge. 5a 160 1:10,00024c d0.. ..d0 .do. 266 do Do.

NOTE 1.--The following oils were used in the above tests: 1d, oil fromGreta, Texas: 2d, oil trom Andrews, Texas; 3d, oil from Thompson, Texas;

4d, oil from Br'ookhaven, Miss; 5d, oil from Village Mills, Texas.

N OIE 2.-Ihe phrase N 0 Treatment as applied to the action of the N114sulfonate alone should be qualified. In some cases the sulfonate maycause some of the emulsified water to drop out of the oil; but theamount is usually so small as to leave the oil still unfit for use.Addition of larger amounts of sulfonate does not further improve thesituation, and may even cause'gelation of some of the emulsion.

NOTE 3.The above tests were conducted in the manner described in atreatise entitled Treating Oil Field Emulsions issued by the AmericanPetroleum Institute in cooperation with the University of Texas (1949).

In examining the results in the above table there are two things whichare particularly striking. One is the and the second (b) that the amountof sludge formed is slight and requires being drawn oif once or twice amonth from a second gun barrel, stock tank or the like. The amount ofoil so discarded is insignificant either from the standpoint of thevalue of the oil or stream contamination.

However, whether justified or not it is frequently the practice to use ademulsifier that produces absolutely bright haze-free oil in the toplayer and yields no interface layer at any time and not even over aperiod of time in the stock tank.

In such cases merely increasing the amount of nonionic demulsifier from1 part to 15,000 emulsion to 1 part to 12,000 for example frequentlycauses no change in respect to either the haze or interface sludge orboth.

However, if an admixture is made as previously described, and themixture used so that one obtains hazefree oil without an interfacelayer, in such instances frequently it win be found that the amount ofsuch demulsifier is substantially thesame as would be requiredin absenceof the ammonium sulfonate, to give a conventionally acceptableresolutionl Stated another'way, the

1 ammonium sulfonate in the admixture appears to contribute little ornothing as far as any demulsifying action in the usual sense of theword, but does either by itselfor by synergistic combination result inthe haze-free, sludge-free emulsion resolution. I

I What has been said immediately preceding may appear inconsistent inlight of what was said in regard to U. S. Patent.1,-299,385, dated April1, 1919, to Rogers.

At the time of the issuance of theRogers patent a ratio of- 1 to 1,000to 1 to'2,000 was considered excellent. Total foreign matter acceptablein pipeline oil at that time ran from 1 to 3% and as a matter of fact asludge layer or interface layer was taken forgrantedin many instances.

, A slight sludge layer or interface layer is illustrated for,

example in a drawing ,whichispart of theU. S. Patent 1,223,659, datedApril 24, "19l7','to Barnickel. v

In light of what has been said previously no attempt is resistant orrefractory sludge which apparently has beenimmune to demulsification inthe usualoperation. Sometimes either type of sludge or both separate outin tanks and become tank bottoms.

We have satisfied ourselves, that in some instances and, perhaps in themajority of instances, the added anionic ammonium sulfonate does not actas a demulsifier but merely acts as a dispersant or a deflocculatingagent for non-emulsified insolubles as noted above. In other words thetrace of impurity that would appear at the interface and the trace ofhaze that appeared in the upper layer when the nonionic demulsifier wasused alone simply was dispersed in a much finer state by virtue of thepresence of the anionic ammonium sulfonate and thus bright oil without asludge layer was obtained and the upper layer still would meetpipelinerequirements for the presence offoreign matter. 7

Having thus described our invention what we claim as new and desiretosecure by Letters Patent isz.

l. A pr oce ss for breaking petroleum emulsions of the water-in-oil typecharacterized by subjecting the emulsion to the action of a demulsifyingagentysaid demulsifying agent being a mixture of at least by weight andnot over 90% byweight of (A) an aromatic solvent-soluble nonionicdemulsifier, containing a plurality of lower oxy-' alkylene groups andat least 10% by weight and not over 40% by weight of (B) ammonium saltsobtained by mono sulfonation and neutralization of a sulphonatablemixture;

said sulphonatable mixture consisting of (a) nonyl phenol foots; saidfoots being characterized by a dinonyl phenol to nonyl phenol ratiowithin the range of'2zl to 3:1 andwith the proviso that said nonylphenol foots contain not less than 90% of nonylated phenols and (b)dodecyl benzene bottoms consisting essentially of didodecyl benzene andotherlpolyalkylated benzenes; the ratio of (a) to (b) being within therange of 2:1 to 4:1.

2. The processor claim 1 with the p'rovisothat the nonionicdemulsifyingagent be obtained by use of at least one olefin oxideselected from the class consisting of ethylene oxide, propylene oxideand butylene oxide.

3. The process ofclairn 1 with the proviso that the 1 nonionicdemulsifier, be obtained by the use of ethylene oxidein combination withpropylene oxide. t

4. A process for breaking petroleum emulsions of the '1! water-in-oiltype characterized by subjecting the emulsion to the action of ademulsifier; said demulsifier being obtained by a mixture of at least60% by weight and not over 90% by weight of (A) an aromaticsolvent-soluble nonionic demulsifier containing a plurality of loweroxyalkylene groups; said demulsifier being obtained by the use ofpropylene oxide and ethylene oxide exclusively with the proviso that notless than 25% by weight of the alkylene oxide reactant be propyleneoxide, and at least by weight and not over 40% by weight of (B) ammoniumsalts obtained by mono sulfonation and neutralization of a sulphonatablemixture; said sulphonatable mixture consisting of (a) nonyl phenolfoots; said foots being characterized by a dinonyl phenol to nonylphenol ratio within the range of 2:1 to 3:1 and with the proviso thatsaid nonyl foots contain not less than 90% of nonylated phenols and (b)dodecyl benzene bottoms consisting essentially of didodecyl benzene andother polyalkylated benzenes; the ratio of (a) to (b) being within therange of 2:1 to 4:1.

5. The process of claim 4 with the proviso that the ratios of the twocomponents, (A) and (B), be roughly 90 parts by Weight and 10 parts byweight; the latter being the ammonium sulfonate.

6. The process of claim 4 with the proviso that the ratios of the twocomponents, (A) and (B), be roughly 80 parts by weight and parts byweight; the latter being the ammonium sulfonate.

7. The process of claim 4 with the proviso that the ratios of the twocomponents, (A) and (B), be roughly 75 parts by weight and parts byweight; the latter being the ammonium sulfonate.

66.7 parts by weight and 33.3 parts by weight; the latter being theammonium sulfonate.

9. The process of claim 4 with the proviso that the ratios of the twocomponents, (A) and (B), be roughly 60 parts by weight and 40 parts byweight; the latter being the ammonium sulfonate.

10. A process for breaking petroleum emulsions of the watcr-in-oil typecharacterized by subjecting the emulsion to the action of a demulsifyingagent; said demulsifying agent being a mixture of at least 60% by weightand not over 90% by weight of (A) an aromatic solvent-soluble nonionicdemulsifier, containing a plurality of lower oxyalkylene groups and atleast 10% by weight and not over 40% by weight of (B) ammonium saltsobtained by mono sulfonation and neutralization of a sulphonatablemixture; said sulphonatable mixture consisting of (a) nonyl phenolfcots; said foots being characterized by a dinonyl phenol to nonylphenol ratio within the range of 2:1 to 3:1 and with the proviso thatsaid nonyl phenol foots contain not less than 90% of nonylated phenolsand (b) dodecyl benzene bottoms consisting essentially of didodecylbenzene and other polyalkylated benzenes; the ratio of (a) to (b) beingwithin the range of 2:1 to 4:1; said emulsion resolution beingcharacterized by a substantially bright upper phase and a sludge-freeinterface.

11. The process of claim 10 with the proviso that the nonionicdemulsifying agent be obtained by use of at least one olefin oxideselected from the class consisting of ethylene oxide, propylene oxideand butylene oxide. 1 12. The process of claim 10 with the proviso thatthe nonionic demulsifier be obtained by the use of ethylene oxide incombination with propylene oxide.

' 13. A process for breaking petroleum emulsions of the water-in-oiltype characterized by subjecting the emulsion to the action of ademulsifier; said demulsifier being obtained' by a mixture of at least60% 'by weight and not over 90% by weight of (A) an aromaticsolvent-soluble nonionic demulsifier containing a plurality of loweroxyalkylene groups; said demulsifier being obtained by the use ofpropylene oxide and ethylene exclusively with the proviso that not lessthan 25% by weight of the alkylene oxide reactant be propylene oxide,and at least 10% by weight and not over 40% by weight of (B) ammoniumsalts obtained by monosulphonation and neutralization of a sulphonatablemixture; said sulphonatable mixture consisting of (a) nonyl phenolfoots; said foots being characterized by a dinonyl phenol to nonylphenol ratio within the range of 2:1 to 3:1 and with the proviso thatsaid. nonyl phenol toots contain not less than 90% of nonylated phenoisand (b) dodecyl benzene bottoms consisting essentially of didodecylbenzene and other polyalkylated' benzenes; the ratio of (a) to (b) beingwithin the range of 2:1 to 4:1; said emulsion resolution beingcharacterized by a substantially bright upper phase and a sludgefreeinterface. 7

14. The process of claim 13 with the proviso that thei ratios of the twocomponents, (A) and (B), be roughly 90 parts by weight and 10 parts byweight; the latter being the ammonium sulfonate.

15. The process of claim 13 with the proviso that the ratios of the twocomponents, (A) and (B), be roughly parts by weight and 20 parts byweight; the latter beingthe ammonium sulfonate.

16. The process of claim 13 with the proviso that the ratios of the twocomponents, (A) and (B), be roughly 75 parts by weight and 25 parts byweight; the latter being the ammonium sulfonate.

17. The process of claim 13 with the proviso that the ratios of the twocomponents, (A) and (B), be roughly 66.7 parts by weight and 33.3 partsby weight; the latter being the ammonium sulfonate.

18. The process of claim 13 with the proviso that the ratios of the twocomponents, (A) and (B), be roughly 60 parts by weight and 40 parts byweight; the latter being the ammonium sulfonate.

19. A process for breaking petroleum emulsions of the water-in-oil typecharacterized by subjecting the emulsion to the action of a demulsifyingagent; said demulsifying agent being a mixture of at least 60% by weightand not over by weight of (A) an aromatic solvent-soluble. nonionicdemulsifier, containing a plurality of lower oxy alkylene groups and atleast 10% by weight and not over 40% by weight of (B) ammonium saltsobtained by mono sulphonation and neutralization of a sulphonatablemixture; said sulphonatable mixture consisting of (a) nonyl phenolfoots; said foots being characterized by a dinonyl. phenol to nonylphenol ratio within the range of 2:1 to 3:1 and with the proviso thatsaid nonyl phenol foots contain not less than 90% of nonylated phenolsand (b) dodecyl benzene bottoms consisting essentially of didodecylbenzene and other polyalkylated benzenes; the ratio of (a) to (b) beingwithin the range of 2:1 to 4:1; said emulsion resolution beingcharacterized by a substantially bright upper phase and a sludge-freeinterface; and with the further proviso that the amount of demulsifierused is sufiicient that the aromatic solvent soluble nonionic de-'mulsifier in the absence of the ammonium sulfonate would cause theemulsion to break.

20. The process of claim 19 with the proviso that the nonionicdemulsifying agent be obtained by use of at least one olefin oxideselected from the class consisting of ethylene oxide, propylene oxideand butylene oxide.

21. The process of claim 19 with the proviso that the nonionicdemulsifier be obtained by the use of ethylene oxide in combination withpropylene oxide.

22. A process for breaking petroleum emulsions of the water-in-oil typecharacterized by subjecting the emulsion to the action of a demulsifier;said demulsifier being ob: tained by a mixture of. at least 60% byweight and not over 90% by weight of (A) an aromatic solvent-solublenonionic demulsifier containing a plurality of lower oxyalkylene groups;said demulsifier being obtained by the use of propylene oxide andethylene oxide exclusively with 13 the proviso that not less than 25% byweight of the alkylene oxide reactant be propylene oxide, and at leastby weight and not over 40% by weight of (B) ammonium salts obtained bymono sulphonation and neutralization of a sulphonatable mixture; saidsulphonatable mixture consisting of (a) nonyl phenol foots; said footsbeing characterized by a dinonyl phenol to nonyl phenol ratio within therange of 2:1 to 3:1 and with the proviso that said nonyl phenol footscontain not less than 90% of nonylated phenols and (b) dodecyl benzenebottoms consisting essentially of didodecyl benzene and otherpolyalkylated benzenes; the ratio of (a) to (b) being Within the rangeof 2:1 to 4:1; said emulsion resolution being characterized by asubstantially bright upper phase and a sludge-free interface; and withthe further proviso that the amount of demulsifier used is sufiicientthat the aromatic solvent soluble nonionic demulsifier in the absence ofthe ammonium sulfonate would cause the emulsion to break.

23. The process of claim 22 with the proviso that the ratios of the twocomponents, (A) and (B), be roughly 90 parts by weight and 10 parts byweight; the latter being the ammonium sulfonate.

24. The process of claim 22 with the proviso that the ratios of the twocomponents, (A) and (B), be roughly 80 parts by weight and parts byweight; thelatter being the ammonium sulfonate.

25. The process of claim 22 with the proviso that the ratios of the twocomponents, (A) and (B), be roughly 75 parts by weight and 25 parts byweight; the latter being the ammonium sulfonate.

26. The process of claim 22 with the proviso that the ratios of the twocomponents, (A) and (B), be roughly 66.7 parts by weight and 33.3 partsby weight; the latter being the ammonium sulfonate.

27. The process of claim 22 with the proviso that the ratios of the twocomponents, (A) and (B), be roughly 60 parts by weight and parts byweight; the latter being the ammonium sulfonate.

References Cited in the file of this patent UNITED STATES PATENTS

1. A PROCESS OF BREAKING PERTOLUM EMULSIONS OF THE WATER-IN-OIL TYPECHARACTEWRIZED BY SUBJECTING THE EMULSION TO THE ACTION OF ADEMULSIFYING AGENT; SAID DEMULSIFYING AGENT BEING A MIXTURE OF AT LEAST60% BY WEIGHT AND NOT OVER 90% BY WEIGHT OF (A) AN AROMATICSOLVENT-SOLUBLE MONIOMIC DEMULSIFIER, CONTAINING A PLURALITY OF LOWEROXYALKYLENE GROUPS AND AT LEAST 10% BY WEIGHT AND NOT OVER 40% BY WEIGHTOF (B) AMMONIUM SALTS OBTAINED BY MONO SULFONATION AND NEUTRALIZATION OFA SULPHONATABLE MIXTURE; SAID SULPHONATION MIXTURE CONSISTING OF (A)DINONYL PHENOL FOOTS; SAID FOOTS BEING CHARACTERIZED BY A DINONYL PHENOLTO NONYL PHENOL RATIO WITHIN THE RANGE OF 2:1 TO 3:1 AND WITH THEPRIVISO THAT SAID NONYL PHENOL CONTAINS NOT LESS THAN 90% OF NONYLATEDPHENO/LS AND (B) DODECYL BENZENE BOTTOMS CONSISTING ESSENTIALLY OFDIDODECYL BENZENE AND OTHER POLYALKYLATED BENZENES; AND THE RATIO OF (A)TO (B) BEING WITHIN THE RANGE OF 2:1 TO 4:1.